• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.23-33
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• 1991

Mn - Zn Ferrite has the natural characteristics of incongruent melting and the zinc oxide evaporation while the crystal is being grown. As a result of these, it comes into existence to be a non-uniform distribution of cations along the crystal growth axis and also Pt particles are usually precipitated into the crystals in Bridgman method since the melt zone is maintained for a long time in the crucible. These have bad effects on the magnetic properties of ferrites. But, to overcome these faults and then acquire the better single crystals. new modified growth method was developed and the growth factors were investigated as following: melt height in the crucible, surface tension and density of melt, the behavior of melt at interface, the shapes of crucible and solid -liquid interface, powder feeding rate, and the crystal growing speed. In additon, when we analyzed the compositional fluctuations of grown crystals, they were supressed within 1.5 mol% $Fe_20_3$, 2 mol% MnO, ZnO respectively with comparing to initial composition of crystal and the microstructures of crystals on the(110) plane were observed by optical microscope through the chemical etching technique and the magnetic properties were determined.

• The Microorganisms and Industry
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• v.19 no.1
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• pp.33-36
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• 1993

세포성장 조절물질 탐색기술 개발 분야의 연구는 학문적으로는 세포성장 조절물질의 작용기작 규명에 의한 유전병의 병리기전, 암의 병리학적인 원인규명과 면역현상의 이해를 통한 생명과학의 기초연구 증진을 이룩할 것이며 세포성장 조절인자의 유전자를 분리하여 유전자 치료법(gene therapy)에 이용하거나 이들 유전자를 발현벡타를 이용해 과발현시켜 난치성 유전병의 치료에 이용하는 등의 임상실험에 활용할 수 있다. 산업적으로는 이들 연구결과를 활용한 신규 항암제 및 면역 조절제 개발기술의 수준 향상에 따른 생물 신의약 개발 분야에서 국제경재력을 제고시키는데 큰 역할을 할 것으로 기대된다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.1
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• pp.1-5
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• 2001

SiC single crystals were grown in the various condition of growth pressure and temperature in the sublimation growth. We observed the growth step morphology and the shapes on the surface of as-grown crystals using an optical microscope, and characterized the co-relations among the growth parameters by adapting the Burton, Carbera and Frank theory(BCF theory)for nucleation and crystal growth.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.1
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• pp.13-23
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• 2024

Purpose: This aim of this study was to demonstrate growth factors that differentiate human mesenchymal stem cells into chondrocytes and to evaluate cell proliferation enhancement by needle size differences. Materials and Methods: Human mesenchymal stem cells were cultured in chondrogenic medium supplemented with BMP-2, BMP-4, BMP-6, BMP-7, BMP-13, FGF-2, FGF-18, IGF-1, TGF-β1, TGF-β2, TGF-β3 and without growth factors for 14, 21, and 28 days. Then, the expression levels of SOX-5, SOX-6, SOX-9 and FOXO1A were comparatively analyzed. Human mesenchymal stem cells were inoculated into culture dishes using 18, 21, and 26 gauge (G) needles, and cell proliferation was measured after 24, 48, and 72 hours, respectively. Results: In addition to the previously known FGF, IGF-1, and TGFβ1,the BMP family growth factors such as BMP-2, BMP-4, BMP-6, and BMP-7 increased the expression of chondrocyte differentiation genes SOX-5, SOX-6, SOX-9, and FOXO1A. At 48 hours, the 26G group, the smallest needle, showed significant cell proliferation improvement compared to the control group and the 18G group. At 72 hours, the 26G group, the smallest needle, showed significant increase in cell proliferation compared to the control group. Conclusion: Through this study, growth factors with the ability to induce chondrocyte differentiation of human mesenchymal stem cells were investigated, and cell proliferation changes by needle size differences were determined.

• Venture DIGEST
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• s.53
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• pp.10-11
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• 2004

공자는 지자요수 인자요산(智者�水仁者�山)이라 했다. 물은 흐르고 흘러 이르지 못하는 곳이 없고 산은 언제나 그 자리에 변함없이 있기 때문에 지혜로운 사람은 물을 좋아하고 인자한 사람은 산을 좋아 한다는 뜻이다. 산을 좋아하는 김재민 대표의 넉넉한 미소를 보면 그 말이 맞는 듯하다. 더존디지털웨어가 초일류기업으로 성장하기 위해 내놓은 비장의 카드 김재민 CEO. 그의 경영이념과 목표에 대해 들어보자.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.2
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• pp.82-89
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• 2013

Purpose: The present study is aimed to evaluate the combined effect of recombinant human bone morphogenetic protein 2 (rhBMP-2) and recombinant human vascular endothelial growth factor (rhVEGF) coated onto anodized implants on osseointeration. Materials and methods: Six New Zealand white rabbit were used in this study. Each animal received 4 implants that were either coated with rhBMP-2 and rhVEGF (Study group) or anodized implant (Control group) in both tibia. This was performed using a randomized split-mouth design. A total 24 implants were used. The implant stability quotient (ISQ) value using resonance frequency analyser and removal torque (RTQ) measurement were investigated at 2 and 8 weeks. The t-test was used for statistical analysis (${\alpha}$=.05). Results: Control and study group showed good osseointegration at 8 weeks. The ISQ and RTQ values of study group were significant compared with the control group at 8 weeks (P<.05). However, No statistical significance was observed at 2 weeks (P>.05). Conclusion: It was concluded that rhBMP-2 with rhVEGF coated onto anodized implants can induce better osseointegration at late healing period.

• Journal of Life Science
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• v.19 no.3
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• pp.327-333
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• 2009

Psoriasis is a well known disorder of keratinization. In this disease, several reports revealed that dermal micro vessels are increased and angiogenic factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are over-expressed. Angiogenesis may play an important role in the progression of psoriasis. Acitretin is widely used as an anti-psoriatic drug because of its potent action on keratinocyte growth and differentiation, but its effects on angiogenesis are uncertain. The goal of this immunohistochemical study was to investigate the effects of acitretin on the expression of VEGF in psoriatic lesions of the skin. We compared the expression levels of VEGF between pre- and post-acitretin treated skin - 10 psoriatic skin lesions and 3 normal (control) skins. The expressions of VEGF in psoriatic skin lesions were significantly higher than in normal control skin. The expressions of VEGF in psoriatic skin lesions post-treatment were lower than those pre-treatment. Acitretin revealed inhibitory effects on angiogenesis by reducing the expression of angiogenic factors such as VEGF in psoriatic skin lesions. We suggest that acitretin may be useful in therapeutic approaches to psoriasis management, possibly related to angiogenesis.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.463-470
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• 1995

Complete prelining of artificial vascular grafts with autologous endothelial cells may be one of the ideal solutions to obtain a nonthrombogenlc blood-contacting surface. To establish an intact endothelial cell monolayer on a prosthetic surface at the time of implantation,a sufficient number of endothelial cells and adequate propagation condition In cell culture are prerequisites. In this experimental study, endothelial cells from microvessels of adult human oriental adipose tissue were enzymatically harvested, and optimal culture conditions for proliferation of the endothelial cells in cell culture were examined. Human oriental adipose tissue was digested with collagenase and endothelial cells were separated from other stromal elements by mesh filtration method. Cultured cells were identified as endothelial cells by immunofluorescent staining for factor VIII-related antigen. Proliferation in usual 20% fetal bovine serum (FBS) medium or medium containing endothelial cell growth factor (ECGF)(5 ng/ml) and heparin (HEP)(1,000 units/ml) were compared,and the effects of adding compounds that increase intracellular cyclic adenosine monophosphate levels, that is,cholera toxin (CT)(1 $\mu\textrm{g}$/ml) and isobutylmethylxanthine (IBMX)(0.2 ml),were also analyzed. In total,following eight media groups were examined. 1) FBS medium + ECGF + HEP, 2) FBS medium + ECGF + HEP+CT, 3) FBS medium+ECGF+HEP+lBMX, 4) FBS medium+ECGF+HEP+CT+ IBMX, 5) FBSmedium, 6) FBS medium +CT, 7) FBS medium + IBMX, 8) FBS medium + CT + IBMX. It was shown that the medium containing ECGF + HEP with or without cholera toxin was most efficient in Stimulating cell proliferation. IBMX was considered to have antagonistic effect to ECGF. Among experimental groups without ECGF and HEP, the addition of cholera toxin and IBMX was shown to significantly potentiate cell proliferation. This results could provide a practical method for use of cultured human endothelial cells for endothelial cell seeding of cardiovascular prosthetic device, particularly in small-diameter vascular grafts.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.885-890
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• 2003

This study was conducted to estimate the growth curve parameters of 253 heads of F2 population produced by inter-crossing F1 from Korean Native boars and Landrace sows, and to estimate the effects of Leptin receptor gene(LEPR) on their growth characteristics. Growth curve parameters were estimated from nonlinear regression using Gompertz model individually. Average mature weight and average maturing rate estimated were 179.69${\pm}$4.40kg and 0.3103${\pm}$0.0043, respectively. The effect of sex was insignificant for all the parameters estimated from Gempertz model(p〉.05), and the effect of calving group was significant for mature weight and maximum growth rate at inflection point (p〈.05). The effect of LEPR genotype were significant for all the growth curve parameters(p〈.05). According from the results of the least squares means of growth curve parameters by LEPR genotypes, mature weight and point of inflection were highest in genotype AA in which the maturing rate was the lowest, and were lowest in genotype DD in which maturing rate was the highest, reversely.

• 건강소식
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• v.35 no.7
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• pp.30-31
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• 2011

"튼튼하게만 자라다오" 모든 부모가 자녀에게 바라는 것이지만, 자녀에게 건강검진을 받게 하는 부모는 드물다. 한창 성장 중인 아이들이 건강하게 성장하기 위해서는 위험 인자를 조기에 발견할 수 있는 건강 검진이 필요하다. 여름방학은 미뤄왔던 건강검진을 받기 좋은 시기다. 여름방학을 맞이해 자녀들에게 필요한 건강검진에 대해 알아보자.